Since I am moving by a buddy who also brews, and has a nice keggle, I thought we could probably use my 8 gal brew pot as a mash tun. This would allow us to do a step mash fairly easily, I think (we each have a burner). Is there anything more to it than just heating and stirring gently until I get to the target temp, then turning the burner off when the temp is right, waiting, and heating to the next step? Should I still use about half the water in the mash and the other half as sparge water? What styles would benefit from this? My guess is that this would be most beneficial for a lager or a wheat beer. Does anyone have any tips for brewing this way? I have previously just done the denny-tun method of brewing.

Stir the whole time! Scorched grains don't taste good (ask me how I know)--unless you really like "Quesadilla" Beer. Also, it is possible that your SRM's may bump up a little higher (especially if you're doing a light colored beer). I just brewed a wheat beer this way that should have been around 5.5 SRM, but ended up around 7.5-8.0 SRM.

Have fun brewing with your buddy--it is much more fun to brew in groups.

My converted kegs have false bottoms. The grain is not in contact with the bottom, You should recirculate when the fire is on, to distribute the heat, and if any small grains bits get through they don't get scorched. A pump is really a good thing to have for hte recirculation.

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Jeff RankertAnn Arbor Brewers GuildAHA Governing Committee BJCP NationalHome-brewing, not just a hobby, it is a lifestyle!

I mash everything over a direct fired kettle/tun. I've used mine enough to know if I set the flame very low and barely kissing the bottom of the tun and stir diligently as soon as the temp I need is reached I need to turn off the flame immediately, but still stir for another couple of minutes. The suggestion to stop a few degrees early the first time out is sound, once you know how your setup behaves you can tweak your procedures.

As far as water, go with at least 1.5 qts/lb to make stirring easier, or if you batch, you could do the half thing. I drain my first runnings and then fly the remainder, but you can do it any way you please.

I think what method you use depends on whether you have a false bottom in the pot or not.

If you do have a false bottom, keeping the heat on low and recirculating is a very even way of heating. It's sort of like a manual RIMS except the heat is applied to the mash tun rather than the recirculating loop, but the effect is pretty much the same. You still have to stir to get the even heating, and it helps to have a more liquid mash. The downside is that stirring the mash can make it harder to recirculate, so be careful about disturbing the grain bed too close to the false bottom.

If you don't have a false bottom, you're essentially doing a decoction. So you definitely have to stir, and you will likely get some color development. A thinner mash is better, since it will keep it from scorching. Use a metal spoon so you can feel the bottom of the kettle for any build-up, which can scorch. A scorched mash tastes like an old ashtray.

German mashes tend to be thinner than English mashes since they often pump them around. It might just be easier for you to start thick and just use boiling water infusions.

If you are going to step mash in one pot without a false bottom and with direct heat, I'd use a relatively thin mash, maybe add some rice hulls, add the heat slowly, and stir constantly. It's important to get the heat evenly distributed, so you'll have to be stirring in a way that mixes the layers (think about making the grain on the top coming into contact with the bottom of the pot). Try to avoid whipping excessive air into it while you're doing this. Keep stirring after you kill the heat; the bottom will still be hotter, and the temperature will continue to rise (like carry-over cooking with meat).

I direct-fire my mash tun (started last year). A pump is handy so you can recirculate AND stir. I started by using a 1-gallon pitcher, but found that I needed to recirculate more than I initially expected and needed to be really patient. My first batch I was not pulling the liquid off fast enough and supe-heated the wort under the grain bed..nothing scorched, but I wound up with a less fermentable wort than desired.

I still have found that patience and low heat are critical to not over-heating the mash. Over the course of the last year I've upgraded my mash tun and now use a pump connected to an AutoSparge for my recirculation. I am pretty happy with that set-up as it worked out on my last batch.

I disagree entirely with you wit...I can hit my temp each and every time exactly regardless of whether I am mashing a 5 gallon batch or a 10 gallon batch a low gravity or a high gravity. I could NEVER get it that exact with infusions...YMMV

Go ahead disagree. To me it is still easier to add the infusion and stir for a short bit than to sit over the mash tun, stir and or circulating, watching the thermometer. I have my system well calibrated and know what my end temperature for each mash step is so I can calculate the exact amount of water to add. People have been very surprised how accurately I hit my temps. Like you said YMMV.

I disagree entirely with you wit...I can hit my temp each and every time exactly regardless of whether I am mashing a 5 gallon batch or a 10 gallon batch a low gravity or a high gravity. I could NEVER get it that exact with infusions...YMMV

MMDV....My mileage does vary! I can hit really exact temps with careful infusions of boiling water.